Sustainable lactic acid production from glycerol via hydrothermal catalysis over highly dispersed cu nanoparticles on bio-tar derived carbon

Abstract

Copper-based catalysts have emerged as promising candidates for the catalytic conversion of glycerol to lactic acid (LA), owing to their cost-effectiveness and high activity. However, optimizing both high conversion efficiency and selectivity in catalytic design remains a significant challenge in the catalytic design for this synthesis. In this study, we developed a highly efficient Cu-based catalyst (Cu/BC) was by optimizing copper loading on biomass tar-derived porous carbon supports. Through systematic investigation of reaction parameters and copper loading effects, the results revealed that the 20 % Cu/BC catalyst achieved exceptional performance, achieving 98.97 % glycerol conversion and 89.88 % LA selectivity under optimized conditions (210°C, 20 h). This superior activity stems from the highly dispersed metallic copper active sites, which enhances reaction kinetics and product selectivity. Notably, excessive copper loading (>20 %) induced metal aggregation, pore blockage, and diffusion limitations, thereby diminishing catalytic performance and promoted side reactions. Kinetic analysis further revealed that the 20 % Cu/BC catalyst exhibited a lower activation energy (110.5 kJ·mol⁻¹) compared to the 25 % Cu/BC counterpart (125.8 kJ·mol⁻¹) in the disappearance of LA, confirming its superior catalytic efficiency. This work not only advances rational design of non-noble metal catalysts but also provides a sustainable strategy for value-added LA production.